Isolation of adipose tissue mesenchymal stem cells without tissue destruction: a non-enzymatic method

Differentiation of placenta-derived MSCs cultured in human platelet lysate: a xenofree supplement

In the last few decades, mesenchymal stem cells (MSCs)-based regenerative therapies in clinical applications have gradually become a hot topic due to their long-term self-renewal and multilineage differentiation ability. In this scenario, placenta (p) has been considered as a good source of MSCs. As a tissue of fetal origin with abundant number of stem cells compared to other sources, their non-invasive acquisition, strong immunosuppression, and lack of ethical concerns make placenta an indispensable source of MSC in stem cell research and therapy. The mesenchymal stem cells were derived from human term placenta (p-MSCs) in xenofree condition using platelet lysate (PL) as a suitable alternative to fetal bovine serum (FBS). Upon isolation, p-MSCs showed plastic adherence with spindle-shaped, fibroblast-like morphology under microscope. p-MSCs flourished well in PL-containing media. Immunophenotyping showed classical MSC markers (> 90%) and lack expression of hematopoietic and HLA-DR (< 1%). Surprisingly, differentiation study showed differentiation of p-MSCs to mature adipocytes in both induced cells and control (spontaneous differentiation), as observed via oil red staining. This is in line with gene expression data where both control and induced cells were positive for visfatin and leptin. Thus, we propose that p-MSCs can be used for clinical applications in the treatment of various chronic and degenerative diseases.

In Vitro Study of a Novel Vibrio alginolyticus-Based Collagenase for Future Medical Application

Mesenchymal stem cells extracted from adipose tissue are particularly promising given the ease of harvest by standard liposuction and reduced donor site morbidity. This study proposes a novel enzymatic method for isolating stem cells using Vibrio alginolyticus collagenase, obtaining a high-quality product in a reduced time. Initially, the enzyme concentration and incubation time were studied by comparing cellular yield, proliferation, and clonogenic capacities. The optimized protocol was phenotypically characterized, and its ability to differentiate in the mesodermal lineages was evaluated. Subsequently, that protocol was compared with two Clostridium histolyticum-based collagenases, and other tests for cellular integrity were performed to evaluate the enzyme's effect on expanded cells. The best results showed that using a concentration of 3.6 mg/mL Vibrio alginolyticus collagenase allows extracting stem cells from adipose tissue after 20 min of enzymatic reaction like those obtained with Clostridium histolyticum-based collagenases after 45 min. Moreover, the extracted cells with Vibrio alginolyticus collagenase presented the phenotypic characteristics of stem cells that remain after culture conditions. Finally, it was seen that Vibrio alginolyticus collagenase does not reduce the vitality of expanded cells as Clostridium histolyticum-based collagenase does. These findings suggest that Vibrio alginolyticus collagenase has great potential in regenerative medicine, given its degradation selectivity by protecting vital structures for tissue restructuration.

Serial Cultivation of an MSC-Like Cell Line with Enzyme-Free Passaging Using a Microporous Titanium Scaffold

In vitro studies on adherent cells require a process of passage to dissociate the cells from the culture substrate using enzymes or other chemical agents to maintain cellular activity. However, these proteolytic enzymes have a negative influence on the viability and phenotype of cells. The mesenchymal stem cell (MSC)-like cell line, C3H10T1/2, adhered, migrated, and proliferated to the same extent on newly designed microporous titanium (Ti) membrane and conventional culture dish, and spontaneous transfer to another substrate without enzymatic or chemical dissociation was achieved. The present study pierced a 10 μm-thick pure Ti sheet with 25 μm square holes at 75 μm intervals to create a dense porous structure with biomimetic topography. The pathway of machined holes allowed the cells to access both sides of the membrane frequently. In a culture with Ti membranes stacked above- and below-seeded cells, cell migration between the neighboring membranes was confirmed using the through-holes of the membrane and contact between the membranes as migration routes. Furthermore, the cells on each membrane migrated onto the conventional culture vessel. Therefore, a cell culture system with enzyme-free passaging was developed.

A Cell Culture Method for the Isolation and Study of Primary Human Dental Pulp Cells

Primary human dental pulp cell (HDPC) cultures contain dental pulp stem cell (DPSC) populations. DPSCs are multipotent mesenchymal cells residing inside the dental pulp where they can contribute to the regenerative potential of this and other tissues throughout the body. These cells are promising tools for cell-based therapies, including regenerative endodontic procedures. HDPCs can be readily isolated and expanded from extracted teeth either by the dental tissue explant method or enzymatic digestion method. This chapter describes the explant method, whereby cells outgrow from dissected pulp tissue, to generate HDPC cultures. We also provide protocols for HDPC passaging, cryopreservation, and basic immunocytochemical characterization.

Analysis of DYRK1B, PPARG, and CEBPB Expression Patterns in Adipose-Derived Stem Cells from Patients Carrying DYRK1B R102C and Healthy Individuals During Adipogenesis

Background: Metabolic syndrome (MetS) is a group of signs and symptoms that are associated with a higher risk of type 2 diabetes mellitus and cardiovascular diseases. The major risk factor for developing MetS is abdominal obesity, which is caused by an increase in adipocyte size or quantity. Increased adipocyte quantity is a result of differentiation of stem cells into adipose tissue. Numerous studies have investigated the expression of key transcription factors, including PPARG and CEBPB during adipocyte differentiation in murine cells such as 3T3-L1 cell lines. To better understand the expression changes during the process of fat accumulation in adipose-derived stem cells (ASCs), we compared the expression of DYRK1B, PPARG, and ẟB in ASCs between the patient (harboring DYRK1B R102C) and control (healthy individuals) groups. Methods: Gene expression was evaluated on the eighth day before induction and days 1, 5, and 15 postinduction. The pluripotent capacity of ASCs and the potential for differentiation into adipocytes were confirmed by flow cytometry analysis of surface markers (CD34, CD44, CD105, and CD90), and Oil Red O staining, respectively. The Expression of DYRK1B, PPARG, and CEBPB were assessed by real-time-polymerase chain reaction in patients and normal individuals. The effects of AZ191, a potent small molecule inhibitor on DYRK1B and CEBPB expression in patients' samples were studied. Result: The expression of DYRK1B kinase and transcription factors (CEBPB and PPARG) are higher in ASCs harboring DYRK1B R102C compared with noncarriers on days 5 and 15 during adipocyte differentiation. These proteins may be helpful to elucidate the mechanisms underlying obesity and obesity-related disorders like MetS. Furthermore, the new compound AZ191 exhibited inhibitory activity toward DYRK1B and CEBPB. We suggest that AZ191 may be helpful in defining the potential roles of DYRK1B and CEBPB in adipogenesis.

Development of hydroxyapatite-coated nonwovens for efficient isolation of somatic stem cells from adipose tissues

Adipose-derived stem cells (ASCs) are an attractive cell source for cell therapy. Despite the increasing number of clinical applications, the methodology for ASC isolation is not optimized for every individual. In this study, we developed an effective material to stabilize explant cultures from small-fragment adipose tissues.

Methods

Polypropylene/polyethylene nonwoven sheets were coated with hydroxyapatite (HA) particles. Adipose fragments were then placed on these sheets, and their ability to trap tissue was monitored during explant culture. The yield and properties of the cells were compared to those of cells isolated by conventional collagenase digestion.

Results

Hydroxyapatite-coated nonwovens immediately trapped adipose fragments when placed on the sheets. The adhesion was stable even in culture media, leading to cell migration and proliferation from the tissue along with the nonwoven fibers. A higher fiber density further enhanced cell growth. Although cells on nonwoven explants could not be fully collected with cell dissociation enzymes, the cell yield was significantly higher than that of conventional monolayer culture without impacting stem cell properties.

Conclusions

Hydroxyapatite-coated nonwovens are useful for the effective primary explant culture of connective tissues without enzymatic cell dissociation.

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Hydroxyapatite-coated nonwovens enable explant culture of adipose tissue.

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ASCs migrated and proliferated from the tissue explants along the fibers in nonwovens.

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Nonwoven explants had significantly higher cell yield than conventional culture.

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Nonwoven culture did not impact stem cell properties of ASCs.

Hydrocortisone Long-term Treatment Effect on Immunomodulatory Properties of Human Adipose-Derived Mesenchymal Stromal/Stem Cells

Cortisol is secreted in prolonged stress and has therapeutic effects in inflammatory diseases. Considering the immunomodulatory effects of mesenchymal stem cells, here we investigated the effect of hydrocortisone (HC) long-term treatment on immunomodulatory properties of human adipose-derived mesenchymal stromal/stem cells (ASCs). Isolated ASCs from healthy subjects were treated with different HC concentrations for 14 days. The effect of HC-treated ASCs on the proliferative response of peripheral blood mononuclear cells (PBMCs) was evaluated in ASCs/2-way mixed leukocyte reaction coculture using 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT)-assay. HC-treated ASCs were further divided into interferon gamma (IFN-γ) stimulated and unstimulated groups. Transforming growth factor beta 1 (TGF-β1) and interleukin (IL)-6 levels were measured in culture supernatants by enzyme-linked immunosorbent assay. Relative expression of cyclooxygenase-2 (COX-2), hepatocyte growth factor, indoleamine dioxygenase, and programmed death-ligand 1 genes was assessed by real-time PCR. Levels of TGF-β1 and COX-2 expression were elevated in unstimulated ASCs, while exposure to high concentration of HC significantly increased TGF-β1 levels and reduced COX-2 expression. Unstimulated HC-5-μM-treated ASCs increased PBMC proliferation ratio on day 2 of coculture compared to the control group (P = 0.05). In IFN-γ stimulated condition, pretreatment with HC-5 μM resulted in a significantly increased IL-6 and significantly decreased COX-2 expression compared to the HC untreated control group. In conclusion, our results showed various alterations of ASC immunomodulatory related features as a result of long-term exposure of different concentrations of HC. It seems that HC at low concentration pushed the balance toward extended immune response in ASCs, while this observation wasn't persistent in ASCs treated with higher concentrations of HC.

Single-cell transcriptome atlas of human mesenchymal stem cells exploring cellular heterogeneity

BACKGROUND

The heterogeneity of mesenchymal stem cells (MSCs) is poorly understood, thus limiting clinical application and basic research reproducibility. Advanced single-cell RNA sequencing (scRNA-seq) is a robust tool used to analyse for dissecting cellular heterogeneity. However, the comprehensive single-cell atlas for human MSCs has not been achieved.

METHODS

This study used massive parallel multiplexing scRNA-seq to construct an atlas of > 130 000 single-MSC transcriptomes across multiple tissues and donors to assess their heterogeneity. The most widely clinically utilised tissue resources for MSCs were collected, including normal bone marrow (n = 3), adipose (n = 3), umbilical cord (n = 2), and dermis (n = 3).

RESULTS

Seven tissue-specific and five conserved MSC subpopulations with distinct gene-expression signatures were identified from multiple tissue origins based on the high-quality data, which has not been achieved previously. This study showed that extracellular matrix (ECM) highly contributes to MSC heterogeneity. Notably, tissue-specific MSC subpopulations were substantially heterogeneous on ECM-associated immune regulation, antigen processing/presentation, and senescence, thus promoting inter-donor and intra-tissue heterogeneity. The variable dynamics of ECM-associated genes had discrete trajectory patterns across multiple tissues. Additionally, the conserved and tissue-specific transcriptomic-regulons and protein-protein interactions were identified, potentially representing common or tissue-specific MSC functional roles. Furthermore, the umbilical-cord-specific subpopulation possessed advantages in immunosuppressive properties.

CONCLUSION

In summary, this work provides timely and great insights into MSC heterogeneity at multiple levels. This MSC atlas taxonomy also provides a comprehensive understanding of cellular heterogeneity, thus revealing the potential improvements in MSC-based therapeutic efficacy.

Generation of two multipotent mesenchymal progenitor cell lines capable of osteogenic, mature osteocyte, adipogenic, and chondrogenic differentiation

Mesenchymal progenitors differentiate into several tissues including bone, cartilage, and adipose. Targeting these cells in vivo is challenging, making mesenchymal progenitor cell lines valuable tools to study tissue development. Mesenchymal stem cells (MSCs) can be isolated from humans and animals; however, obtaining homogenous, responsive cells in a reproducible fashion is challenging. As such, we developed two mesenchymal progenitor cell (MPC) lines, MPC1 and MPC2, generated from bone marrow of male C57BL/6 mice. These cells were immortalized using the temperature sensitive large T-antigen, allowing for thermal control of proliferation and differentiation. Both MPC1 and MPC2 cells are capable of osteogenic, adipogenic, and chondrogenic differentiation. Under osteogenic conditions, both lines formed mineralized nodules, and stained for alizarin red and alkaline phosphatase, while expressing osteogenic genes including Sost, Fgf23, and Dmp1. Sost and Dmp1 mRNA levels were drastically reduced with addition of parathyroid hormone, thus recapitulating in vivo responses. MPC cells secreted intact (iFGF23) and C-terminal (cFGF23) forms of the endocrine hormone FGF23, which was upregulated by 1,25 dihydroxy vitamin D (1,25D). Both lines also rapidly entered the adipogenic lineage, expressing adipose markers after 4 days in adipogenic media. MPC cells were also capable of chondrogenic differentiation, displaying increased expression of cartilaginous genes including aggrecan, Sox9, and Comp. With the ability to differentiate into multiple mesenchymal lineages and mimic in vivo responses of key regulatory genes/proteins, MPC cells are a valuable model to study factors that regulate mesenchymal lineage allocation as well as the mechanisms that dictate transcription, protein modification, and secretion of these factors.

Methods of Modification of Mesenchymal Stem Cells and Conditions of Their Culturing for Hyaline Cartilage Tissue Engineering

The use of mesenchymal stromal cells (MSCs) for tissue engineering of hyaline cartilage is a topical area of regenerative medicine that has already entered clinical practice. The key stage of this procedure is to create conditions for chondrogenic differentiation of MSCs, increase the synthesis of hyaline cartilage extracellular matrix proteins by these cells and activate their proliferation. The first such works consisted in the indirect modification of cells, namely, in changing the conditions in which they are located, including microfracturing of the subchondral bone and the use of 3D biodegradable scaffolds. The most effective methods for modifying the cell culture of MSCs are protein and physical, which have already been partially introduced into clinical practice. Genetic methods for modifying MSCs, despite their effectiveness, have significant limitations. Techniques have not yet been developed that allow studying the effectiveness of their application even in limited groups of patients. The use of MSC modification methods allows precise regulation of cell culture proliferation, and in combination with the use of a 3D biodegradable scaffold, it allows obtaining a hyaline-like regenerate in the damaged area. This review is devoted to the consideration and comparison of various methods used to modify the cell culture of MSCs for their use in regenerative medicine of cartilage tissue.

The Current Challenges on Spray-Based Cell Delivery to the Skin Wounds

Cell delivery through spray instruments is a promising and effective method in tissue engineering and regenerative medicine. It is used for treating different acute and chronic wounds, including burns with different etiologies, chronic diabetic or venous wounds, postcancer surgery, and hypopigmentation disorders. Cell spray can decrease the needed donor site area compared with conventional autologous skin grafting. Keratinocytes, fibroblasts, melanocytes, and mesenchymal stem cells are promising cell sources for cell spray procedures. Different spray instruments are designed and utilized to deliver the cells to the intended skin area. In an efficient spray instrument, cell viability and wound coverage are two determining parameters influenced by various physical and biological factors such as air pressure, spraying distance, viscosity of suspension, stiffness of the wound surface, and velocity of impact. Besides, to improve cell delivery by spray instruments, some matrices and growth factors can be added to cell suspensions. This review focuses on the different types of cells and spray instruments used in cell delivery procedures. It also discusses physical and biological parameters associated with cell viability and wound coverage in spray instruments. Moreover, the recent advances in codelivery of cells with biological glues and growth factors, as well as clinical translation of cell spraying, have been reviewed. Impact statement Skin wounds are a group of prevalent injuries that can lead to life-threatening complexities. As a focus of interest, stem cell therapy and spray-based cell delivery have effectively decreased associated morbidity and mortality. This review summarizes a broad scope of recent evidence related to spray-based cell therapy, instruments, and approaches adopted to make the process more efficient in treating skin wounds. An overview including utilized cell types, clinical cases, and current challenges is also provided.

Therapeutic mesenchymal stromal stem cells: Isolation, characterization and role in equine regenerative medicine and metabolic disorders

Mesenchymal stromal cells (MSC) have become a popular treatment modality in equine orthopaedics. Regenerative therapies are especially interesting for pathologies like complicated tendinopathies of the distal limb, osteoarthritis, osteochondritis dissecans (OCD) and more recently metabolic disorders. Main sources for MSC harvesting in the horse are bone marrow, adipose tissue and umbilical cord blood. While the acquisition of umbilical cord blood is fairly easy and non-invasive, extraction of bone marrow and adipose tissue requires more invasive techniques. Characterization of the stem cells as a result of any isolation method, is also a crucial step for the confirmation of the cells' stemness properties; thus, three main characteristics must be fulfilled by these cells, namely: adherence, expression of a series of well-defined differentiation clusters as well as pluripotency. EVs, resulting from the paracrine action of MSCs, also play a key role in the therapeutic mechanisms mediated by stem cells; MSC-EVs are thus largely implicated in the regulation of proliferation, maturation, polarization and migration of various target cells. Evidence that EVs alone represent a complex network 0involving different soluble factors and could then reflect biophysical characteristics of parent cells has fuelled the importance of developing highly specific techniques for their isolation and analysis. All these aspects related to the functional and technical understanding of MSCs will be discussed and summarized in this review.

Use of human induced pluripotent stem cells for cartilage regeneration in vitro and within chondral defect models of knee joint cartilage in vivo: a Preferred Reporting Items for Systematic Reviews and Meta-Analyses systematic literature review

BACKGROUND AIMS

Articular cartilage has limited regenerative ability when damaged through trauma or disease. Failure to treat focal chondral lesions results in changes that inevitably progress to osteoarthritis. Osteoarthritis is a major contributor to disability globally, which results in significant medical costs and lost wages every year. Human induced pluripotent stem cells (hiPSCs) have long been considered a potential autologous therapeutic option for the treatment of focal chondral lesions. Although there are significant advantages to hiPSCs over other stem cell options, such as mesenchymal and embryonic stem cells, there are concerns regarding their ability to form bona fide cartilage and their tumorgenicity in vivo.

METHODS

The authors carried out a systematic literature review on the use of hiPSCs to produce differentiated progeny capable of producing high-quality cartilage in vitro and regenerate cartilage in osteochondral defects in vivo in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eight studies were included in the review that used hiPSCs or their derived progeny in xenogeneic transplants in animal models to regenerate cartilage in osteochondral defects of the knee joint. The in vitro-differentiated, hiPSC-derived and in vivo defect repair ability of the hiPSC-derived progeny transplants were assessed.

RESULTS

Most studies reported the generation of high-quality cartilage-producing progeny that were able to successfully repair cartilage defects in vivo. No tumorigenicity was observed.

CONCLUSIONS

The authors conclude that hiPSCs offer a valuable source of cartilage-producing progeny that show promise as an effective cell-based therapy in treating focal chondral lesions.

Towards the standardization of methods of tissue processing for the isolation of mesenchymal stromal cells for clinical use

Multipotent mesenchymal stromal cells (MSCs) are currently the most extensively studied type of adult stem cells in advanced stages of development in the field of regenerative medicine. The biological properties of MSCs have generated great hope for their therapeutic use in degenerative and autoimmune conditions that, at present, lack effective treatment options. Over the last decades, MSCs have been typically obtained from adult bone marrow, but the extraction process is highly invasive and the quality and numbers of isolated cells is drastically influenced by patient age, medication and associated comorbidities. Therefore, there is currently an open discussion on the convenience of allogeneic over autologous treatments, despite potential disadvantages such as rejection by the host. This shift to the allogeneic setting entails the need for high production of MSCs to ensure availability of sufficient cell numbers for transplantation, and therefore making the search for alternative tissue sources of highly proliferative MSC cultures with low levels of senescence occurrence, which is one of the greatest current challenges in the scale up of therapeutic cell bioprocessing. Herein we (i) present the main isolation protocols of MSCs from bone marrow, adipose tissue and Wharton’s jelly of the umbilical cord; and (ii) compare their qualities from a bioprocess standpoint, addressing both quality and regulatory aspects, in view of their anticipated clinical use.

Rapid, practical and safe isolation of adipose derived stem cells

We compared migration, proliferation, growth curve, confluency and differentiation into adipogenic, osteogenic and chondrogenic cell lineages of mesenchymal stem cells derived from adipose tissue cultured in scratched and nonscratched cell culture flasks. Mesenchymal stem cells were isolated from rat adipose tissue using a nonenzymatic method. We investigated two groups. For the control group, minced adipose tissue was implanted conventionally onto the surface of standard plastic cell culture flasks. For the experimental group, the tissues were cultured in flasks with a scratched surface. We found that scratched flasks promoted cell migration, proliferation and confluency. Our findings suggest that scratched flasks may be used to ensure rapid, practical and safe isolation of adipose tissue-derived stem cells.

Labial Stem Cell Extract Mitigates Injury to Irradiated Salivary Glands

Stem cell-based therapies could provide a permanent treatment for salivary gland (SG) hypofunction caused by ionizing radiation (IR) injury. However, current challenges for SG stem cells to reach the clinic include surgical invasiveness, amount of tissue needed, cell delivery, and storage methods. The objective of this study was to develop a clinically less invasive method to isolate and expand human SG stem cells and then to obtain a cell-free extract to be used as a therapy for IR-injured SGs. Human labial glands were biopsied, and labial stem cells (LSCs) were expanded by explant culture. The LSC extract (LSCE) was obtained by releasing the cellular components after 3 freeze-thaw cycles and 17,000g force centrifugation. LSCE was injected intravenously into mice that had their SGs injured with 13-Gy IR. Positive (non-IR) and negative (IR) control mice received injections of saline (vehicle control). Three pieces of labial glands (0.1 g weight) could expand 1 to 2 million cells. LSCs had a doubling time of 18.8 h; could differentiate into osteocytes, adipocytes, and chondrocytes; and were positive for mesenchymal stem cell markers. Both angiogenic (FGF-1, FGF-2, KGF, angiopoietin, uPA, VEGF) and antiangiogenic factors (PAI-1, TIMP-1, TSP-1, CD26) were detected in LSCE. In addition, some angiogenic factors (PEDF, PTX3, VEGF) possessed neurotrophic functions. Mice treated with LSCE had 50% to 60% higher salivary flow rate than saline-treated mice at 8 and 12 wk post-IR. Saliva lag time measurements also confirmed that LSCE restored SG function. Histologic analyses of parotids and submandibular glands reported comparable numbers of acinar cells, blood vessels, and parasympathetic nerves and cell proliferation rates in sham IR and LSCE-treated mice, though significantly lower in saline-treated mice. An explant culture method can harvest a large number of LSCs from small pieces of labial glands. LSCE showed clinical potential to mitigate IR-injured SGs.

Synovium-Derived Mesenchymal Stem Cell Transplantation in Cartilage Regeneration: A PRISMA Review of in vivo Studies

Articular cartilage damaged through trauma or disease has a limited ability to repair. Untreated, focal lesions progress to generalized changes including osteoarthritis. Musculoskeletal disorders including osteoarthritis are the most significant contributor to disability globally. There is increasing interest in the use of mesenchymal stem cells (MSCs) for the treatment of focal chondral lesions. There is some evidence to suggest that the tissue type from which MSCs are harvested play a role in determining their ability to regenerate cartilage in vitro and in vivo. In humans, MSCs derived from synovial tissue may have superior chondrogenic potential. We carried out a systematic literature review on the effectiveness of synovium-derived MSCs (sMSCs) in cartilage regeneration in in vivo studies in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. Twenty studies were included in our review; four examined the use of human sMSCs and 16 were conducted using sMSCs harvested from animals. Most studies reported successful cartilage repair with sMSC transplantation despite the variability of animals, cell harvesting techniques, methods of delivery, and outcome measures. We conclude that sMSC transplantation holds promise as a treatment option for focal cartilage defects. We believe that defining the cell population being used, establishing standardized methods for MSC delivery, and the use of objective outcome measures should enable future high quality studies such as randomized controlled clinical trials to provide the evidence needed to manage chondral lesions optimally.

Melanoma cancer stem-like cells: Optimization method for culture, enrichment and maintenance

Malignant Melanoma is known for being one of the most aggressive cancers with an incidence that increases every year. Cancer stem cells (CSCs) are involved in the resistance to therapeutic treatments, the metastatic process, and the patient's relapses. Thus, it is of vital importance for researchers to find the methodology that allows us to obtain enriched subpopulations that maintain their stem-like properties without differentiating over time. In the present manuscript, our objective was to compare the ability of conditioned medium obtained from human mesenchymal stem cells (MSCs) isolated by enzymatic and non-enzymatic methods for the enrichment and maintenance of melanoma CSCs. Our results showed for the first time that MSCs isolated by less aggressive methodology displayed higher CSCs enrichment and maintenance capacity. Because they do not undergo enzymatic and proteolytic stress, MSCs produce a greater amount of signalling molecules, helping to improve the phenotype characteristics of CSCs and keep them over time.

In vitro heterogeneity of porcine adipose tissue-derived stem cells

Tissue-specific adult stem cells (ASC) are heterogeneous and characterized by a mix of progenitor cells that produce cells at various stages of differentiation, and ultimately different terminally differentiated cells. Understanding the heterogeneity of ASCs may lead to the development of improved protocols of cell isolation and optimized cell therapy clinical protocols. Using a combination of enzymatic and explant culture protocols, we obtained pADSC population, which is composed by two distinct morphologies: fibroblast-like cells (FLCs) and endothelial-like cells (ELCs). Both cell sub-types efficiently formed colonies, expressed CD90⁺/CD105⁺/CD44⁺, and differentially expressed such markers such as Nestin, Vimentin, Fibronectin, Cytokeratin, Connexin 43, CD31, CD34 and CD146 as well as the pluripotent stem cell markers Oct-4, Nanog and Sox2. Mixed populations of pADSCs did not lose their multipotentiality and the cells were able to undergo osteogenic, chondrogenic, adipogenic and myogenic differentiation. Furthermore, the mixed population spontaneously formed capillary tube structures. Our findings suggest that different subpopulations can be isolated from adipose tissue and that the ADSCs need to be better evaluated using a wide panel of different markers related to cell differentiation, which is important for stem cell therapy and regenerative medicine, particularly for advanced stem cells therapies - products that are currently under investigation or even use.

Long term explant culture for harvesting homogeneous population of human dental pulp stem cells

Dental pulp stem cells have emerged as a preferred source of mesenchymal stem cells, because of its easy availability and high stem cell content. Dental pulp is a specific fibrous tissue that contains heterogeneous populations of odontoblasts, fibroblasts, pericytes, progenitors, stem cells, leukocytes and neuronal cells. In this study, we propose sustained explant culture as a simple, economical and efficient process to isolate dental pulp stem cells from human Dental pulp Tissue. Historically explant cultures were used to get fibroblast cells from embryonic chick heart using plasma clot cultures. The subculture was performed by lifting mother explant (original explant) and grafting it in a new plasma clot. We modified this age old technique to suit the modern times. Here we demonstrate for the first time that the mother explant (E0) of human dental pulp tissue could be sub-cultured consecutively seven times (E7) without displacement. This technique is highly reproducible and permits growth and proliferation of dental pulp stem cells yielding an enriched homogeneous mesenchymal stem cells population in the first passage itself as revealed by surface marker expression. These dental pulp stem cells exhibit differentiation into adipogenic, chondrogenic and osteogenic lineage revealing their mesenchymal stem cell nature. We propose that dental pulp stem cells isolated by sustained explant culture are phenotypically and functionally comparable to those obtained by enzymatic method. It is a simple, inexpensive and gentle method, which may be preferred over the conventional techniques for obtaining stem cells from other tissue sources as well especially in cases of limited starting material.

Addressing the Manufacturing Challenges of Cell-Based Therapies

Exciting developments in the cell therapy field over the last decades have led to an increasing number of clinical trials and the first cell products receiving marketing authorization. In spite of substantial progress in the field, manufacturing of cell-based therapies presents multiple challenges that need to be addressed in order to assure the development of safe, efficacious, and cost-effective cell therapies.The manufacturing process of cell-based therapies generally requires tissue collection, cell isolation, culture and expansion (upstream processing), cell harvest, separation and purification (downstream processing), and, finally, product formulation and storage. Each one of these stages presents significant challenges that have been the focus of study over the years, leading to innovative and groundbreaking technological advances, as discussed throughout this chapter.Delivery of cell-based therapies relies on defining product targets while controlling process variable impact on cellular features. Moreover, commercial viability is a critical issue that has had damaging consequences for some therapies. Implementation of cost-effectiveness measures facilitates healthy process development, potentially being able to influence end product pricing.Although cell-based therapies represent a new level in bioprocessing complexity in every manufacturing stage, they also show unprecedented levels of therapeutic potential, already radically changing the landscape of medical care.

Zinc Sulphate Mediates the Stimulation of Cell Proliferation of Rat Adipose Tissue-Derived Mesenchymal Stem Cells Under High Intensity of EMF Exposure

Unlike the role of mesenchymal stem cells (MSCs) in regenerative medicine, their application in cell therapy can be complicated by factors such as a reduction in the proliferation potential, senescent tendency of MSCs to expand, and an age-dependent decline in their number and functions. It was shown that there is an association between exposure to electromagnetic fields (EMFs) and response to stress, cell proliferation, aging, and cell death. Furthermore, the zinc ion, as an essential trace element, was reported to be involved in the regulation of the growth and cell proliferation. In this report, ratadipose tissue-derived mesenchymal stem cells (rADSCs) were randomly divided into four groups-group I (control without any ZnSO₄ and EMF); group II (ZnSO₄ treatment without EMF exposed); group III (EMF exposed without ZnSO₄); and group ІV (EMF exposed with ZnSO₄)-to evaluate whether 0.14 μg/ml Zinc sulfate (ZnSO₄) could affect cell proliferation of rADSCs under extremely low frequency-electromagnetic field (ELF-EMF). The methyl thiazoltetrazolium (MTT) method was used to determine the cell proliferation of rADSCs following exposure to ELF-EMF in the presence of ZnSO₄. The immunocytochemistry method as well as flow-cytometry was used to identify the cell surface markers. Next, oil red O, alizarin red, toluidine blue, and cresyl violet staining was done to evaluate the adipogenic, osteogenic, chondrogenic, and neurogenic differentiation of rADSCs as the pluripotent capacity of rADSCs, respectively. The results showed that an exposure to ELF-EMF caused a decrease in the proliferation of rADSCs. However, the ZnSO₄ supplementation significantly increased the cell proliferation of ELF-EMF-exposed rADSCs. In addition, in the presence of 0.14 μg/ml ZnSO₄, rADSCs appeared to be growing faster than the control group and ZnSO₄ significantly decreased the doubling time of ELF-EMF-exposed rADSCs. It seems that ZnSO₄ would be a good element to induce the cell proliferation of ELF-EMF-exposed rADSCs.

Revisiting the Advances in Isolation, Characterization and Secretome of Adipose-Derived Stromal/Stem Cells

Adipose-derived stromal/stem cells (ASCs) seems to be a promising regenerative therapeutic agent due to the minimally invasive approach of their harvest and multi-lineage differentiation potential. The harvested adipose tissues are further digested to extract stromal vascular fraction (SVF), which is cultured, and the anchorage-dependent cells are isolated in order to characterize their stemness, surface markers, and multi-differentiation potential. The differentiation potential of ASCs is directed through manipulating culture medium composition with an introduction of growth factors to obtain the desired cell type. ASCs have been widely studied for its regenerative therapeutic solution to neurologic, skin, wound, muscle, bone, and other disorders. These therapeutic outcomes of ASCs are achieved possibly via autocrine and paracrine effects of their secretome comprising of cytokines, extracellular proteins and RNAs. Therefore, secretome-derivatives might offer huge advantages over cells through their synthesis and storage for long-term use. When considering the therapeutic significance and future prospects of ASCs, this review summarizes the recent developments made in harvesting, isolation, and characterization. Furthermore, this article also provides a deeper insight into secretome of ASCs mediating regenerative efficacy.

The Use of Vibrational Energy to Isolate Adipose-Derived Stem Cells

Background:

Adipose-derived stem cell (ADSC)–based treatments have the potential to treat numerous soft-tissue pathologies. It would be beneficial to develop an efficient and reliable intraoperative, nonenzymatic method of isolating ADSCs for clinical use. This study aims to determine the (1) viability and proliferative capacity of ADSCs after exposure to vibrational energies and (2) efficacy of vibrational energy as a method of ADSC isolation from surgically harvested infrapatellar fat pad (IFP).

Methods:

Cultured ADSCs were exposed to 15 minutes of vibration (60 Hz) with displacements ranging from 0 to 2.5 mm to assess cell viability and proliferation. Then, arthroscopically harvested adipose tissue (IFP; n = 5 patients) was filtered and centrifuged to separate the stromal vascular fraction, which was exposed to 15 minutes of vibration (60 Hz; 1.3 mm or 2.5 mm displacement). A viability analysis was then performed along with proliferation and apoptosis assays.

Results:

Vibration treatment at all displacements had no effect on the viability or proliferation of the cultured ADSCs compared with controls. There was an increased apoptosis rate between the 2.5 mm displacement group (7.53%) and controls (5.17%; P < 0.05) at day 1, but no difference at days 2, 3, and 14. ADSCs were not isolated from the IFP tissue after vibration treatment.

Conclusions:

ADSCs maintained viability and proliferative capacity after 15 minutes of vibration at 60 Hz and 2.5 mm displacement. ADSCs were not isolated harvested IFP tissue after the application of vibrational energy.

Effect of zoledronate, a third-generation bisphosphonate, on proliferation and apoptosis of human dental pulp stem cells

Clinical use of zoledronate is accompanied by osteonecrosis of the jaw but the pathogenesis is not well understood. We assumed that zoledronate may have cytotoxicity against stem cells of the oral cavity and in this way helps to initiate or promote osteonecrosis. Dental pulp stem cells (DPSCs) and gingival fibroblasts (GFs) were isolated from volunteers who were undergoing a third molar extraction. The proliferation of DPSCs and GFs was evaluated using the thiazolyl blue tetrazolium bromide assay. The effect of zoledronate on apoptosis was determined by propidium iodide staining and Western blotting analysis. Incubation with zoledronate for 72 h and 7 days significantly decreased proliferation of DPSCs and GFs at concentrations of more than 0.4 μmol/L (p < 0.001). The IC50 of zoledronate was lower for DPSCs than for GFs (0.92 versus 3.5 μmol/L for 7 days of treatment). After 72 h of treatment with zoledronate, the percentage of apoptotic DPSCs significantly increased, which was accompanied by an increased level of pro-apoptotic proteins caspase-3 and Bax and decreased the level of the anti-apoptotic protein Bcl-2. In conclusion, zoledronate has anti-proliferative and pro-apoptotic effects in DPSCs. These effects may be involved in promoting zoledronate-induced osteonecrosis and suggest an unfavorable impact of this drug on regenerative potentials of the body stem cells.

Physiological effects of proinsulin-connecting peptide in human subcutaneous adipose tissue

Recent studies suggest that proinsulin-connecting peptide (C-peptide) may exhibit characteristics of a hormone and show physiological functions in various tissues. This study was aimed to determine whether C-peptide could be involved in the regulation of lipolysis, adiponectin release, and function of mesenchymal stem cells (MSCs) in adipose tissue. Human subcutaneous adipose tissue was cultured in the presence of C-peptide. The level of lipolysis was determined by glycerol measurement in the conditioned media. Effect of C-peptide on adiponectin secretion was evaluated in differentiated adipocytes. The adipogenic and osteogenic abilities of adipose MSCs were evaluated using oil red and alizarin red staining, respectively. The tetrazolium bromide test was conducted for evaluating the effect of C-peptide on MSCs proliferation. C-peptide induced a significant decrease in basal lipolysis at concentrations of 8 and 16 nM (p < 0.05). It had no significant effects on isoproterenol-stimulated lipolysis, adiponectin secretion, and adipogenic or osteogenic differentiation of MSCs. At a concentration of 4 nM, this peptide significantly increased the proliferative capability of MSCs (p < 0.05). These results suggest that C-peptide has some physiological effects in human subcutaneous adipose tissue and contributes to the regulation of basal lipolysis and pool of MSCs.

In Vitro Cytotoxicity of a New Nano Root Canal Sealer on Human Gingival Fibroblasts

Introduction:

The aim of this in vitro study was to evaluate the cytotoxicity of a new nano zinc-oxide eugenol (NZOE) sealer on human gingival fibroblasts (HGFs) compared with Pulpdent (micro-sized ZOE sealer) and AH-26 (resin-based sealer).

Methods and Materials:

The Pulpdent, AH-26, and NZOE sealers were prepared and exposed to cell culture media immediately after setting, and 24 h and one week after setting. Then, the primary cultured HGFs were incubated for 24 h with different dilutions (1:1 to 1:32) of each sealer extract. Cell viability was evaluated by methyl thiazolyl diphenyl tetrazolium bromide (MTT) assay. The results were compared using two-way analysis of variance followed by Tukey’s post hoc test. The level of significance was set at 0.05.

Results:

All sealer extracts, up to 32 times dilutions, showed cytotoxicity when exposed to HGF immediately after setting. The extracts obtained 24 h or one week after setting showed lower cytotoxicity than extracts obtained immediately after setting. At all setting times, NZOE showed lower cytotoxicity than Pulpdent and AH-26. While one-week extracts of NZOE had no significant effect on the viability of HGF at dilutions 1:4 to 1:32, both Pulpdent and AH-26 decreased the cell viability at dilutions of 1:4 and 1:8.

Conclusion:

NZOE exhibited lower cytotoxicity compared to Pulpdent and AH-26 on HGF and has the potential to be considered as a new root canal filling material.

Fibroblast Growth Factor 1-Transfected Adipose-Derived Mesenchymal Stem Cells Promote Angiogenic Proliferation

The aim of this study was to investigate, for the first time, the effects of using adipose-derived mesenchymal stem cells (AD-MSCs) transfected with an episomal plasmid encoding fibroblast growth factor 1 (FGF1) (AD-MSCsFGF1), in providing the microenvironment required for angiogenic proliferation. The isolated rat AD-MSCs were positive for mesenchymal (CD29 and CD90) and negative for hematopoietic (CD34 and CD45) surface markers. Adipogenic and osteogenic differentiation of the AD-MSCs also occurred in the proper culture media. The presence of FGF1 in the conditioned medium from the AD-MSCsFGF1 was confirmed by Western blotting. G418 and PCR were used for selection of transfected cells and confirmation of the presence of FGF1 mRNA, respectively. Treatment with the AD-MSCFGF1-conditioned medium significantly increased the NIH-3T3 cell proliferation and human umbilical vein endothelial cell (HUVEC) tube formation compared to conditioned medium from nontransfected AD-MSCs (p < 0.001). In conclusion, the AD-MSCsFGF1 efficiently secreted functional FGF1, which promoted angiogenic proliferation. Using AD-MSCsFGF1 may provide a useful strategy in cell therapy, which can merge the beneficial effects of stem cells with the positive biological effects of FGF1 in various disorders, especially tissue defects, neurodegenerative, cardiovascular and diabetes endocrine pathologies, which remain to be tested in preclinical and clinical studies.

Explant culture: An advantageous method for isolation of mesenchymal stem cells from human tissues

Mesenchymal stem cell (MSC) research progressively moves towards clinical phases. Accordingly, a wide range of different procedures were presented in the literature for MSC isolation from human tissues; however, there is not yet any close focus on the details to offer precise information for best method selection. Choosing a proper isolation method is a critical step in obtaining cells with optimal quality and yield in companion with clinical and economical considerations. In this concern, current review widely discusses advantages of omitting proteolysis step in isolation process and presence of tissue pieces in primary culture of MSCs, including removal of lytic stress on cells, reduction of in vivo to in vitro transition stress for migrated/isolated cells, reduction of price, processing time and labour, removal of viral contamination risk, and addition of supporting functions of extracellular matrix and released growth factors from tissue explant. In next sections, it provides an overall report of technical highlights and molecular events of explant culture method for isolation of MSCs from human tissues including adipose tissue, bone marrow, dental pulp, hair follicle, cornea, umbilical cord and placenta. Focusing on informative collection of molecular and methodological data about explant methods can make it easy for researchers to choose an optimal method for their experiments/clinical studies and also stimulate them to investigate and optimize more efficient procedures according to clinical and economical benefits.

Differentiation potential of human adipose tissue derived stem cells into photoreceptors through explants culture and enzyme methods

AIM

To investigate the retinal photoreceptor differentiation potential of human orbital adipose tissue-derived stem cells (ADSCs) generated by enzyme (EN) and explant (EX) culture methods.

METHODS

We investigated potentials of human orbital ADSCs to differentiate into photoreceptors through EN and EX culture methods. EN and EX orbital ADSCs were obtained from the same donor during rehabilitative orbital decompression, and then were subject to a 3-step induction using Noggin, DKK-1, IGF-1 and b-FGF at different time points for 38d. Stem cell, eye-field and photoreceptor-related gene and protein markers were measured by reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescent (IMF) staining.

RESULTS

Both EX and EN orbital ADSCs expressed CD133, a marker of cell differentiation. Moreover, PAX6 and rhodopsin, markers of the retinal progenitor cells, were detected from EX and EN orbital ADSCs. In EX orbital ADSCs, PAX6 mRNA was detected on the 17^th day and then the rhodopsin mRNA was detected on the 24^th day. In contrast, the EN orbital ADSCs expressed PAX6 and rhodopsin mRNA on the 31^st day. EX orbital ADSCs expressed rhodopsin protein on the 24^th day, while EN orbital ADSCs expressed rhodopsin protein on the 31^st day.

CONCLUSION

Orbital ADSCs isolated by direct explants culture show earlier and stronger expressions of markers towards eye field and retinal photoreceptor differentiation than those generated by conventional EN method.

Production of Bovine Embryos and Calves Cloned by Nuclear Transfer Using Mesenchymal Stem Cells from Amniotic Fluid and Adipose Tissue

The less differentiated the donor cells are used in nuclear transfer (NT), the more easily are they reprogrammed by the recipient cytoplasm. In this context, mesenchymal stem cells (MSCs) appear as an alternative to donor nuclei for NT. The amniotic fluid and adipose tissue are sources of MSCs that have not been tested for the production of cloned embryos in cattle. The objective of this study was to isolate, characterize, and use MSCs derived from amniotic fluid (MSC-AF) and adipose tissue (MSC-AT) to produce cloned calves. Isolation of MSC-AF was performed using in vivo ultrasound-guided transvaginal amniocentesis, and MSC-AT were isolated by explant culture. Cellular phenotypic and genotypic characterization by flow cytometry, immunohistochemistry, and RT-PCR were performed, as well as induction in different cell lineages. The NT was performed using MSC-AF and MSC-AT as nuclear donors. The mesenchymal markers of MSC were expressed in bovine MSC-AF and MSC-AT cultures, as evidenced by flow cytometry, immunohistochemistry, and RT-PCR. When induced, these cells differentiated into osteocytes, chondrocytes, and adipocytes. Embryo production was similar between the cell types, and two calves were born. The calf from MSC-AT was born healthy, and this fact opens a new possibility of using this type of cell to produce cloned cattle by NT.

A rapid sonication based method for preparation of stromal vascular fraction and mesenchymal stem cells from fat tissue

Introduction: Much attention has been paid to the idea of cell therapy using stem cells from different sources of the body. Fat-derived stem cells that are called adipose derived stem cells (ADSCs) from stromal vascular fraction (SVF) are the subject of many studies in several cell therapy clinical trials. Despite production of some GMP-grade enzymes to isolate SVF for clinical trials, there are critical conditions like inconsistency in lot-to-lot enzyme activity, endotoxin residues, other protease activities and cleavage of some cell surface markers which significantly narrow the options. So we decided to develop a new method via sonication cavitation to homogenize fat tissue and disrupt partially adipose cells to obtain SVF and finally ADSCs at a minimum of time and expenses.

Methods: The fat tissue was chopped in a sterile condition by a blender mixer and then sonicated for 2 s before centrifugation. The next steps were performed as the regular methods of SVF harvesting, and then it was characterized using flow cytometry.

Results: Analysis of the surface markers of the cells revealed similar sets of surface antigens. The cells showed slightly high expression of CD34, CD73 and CD105. The differentiation capacity of these cells indicates that multipotent properties of the cells are not compromised after sonication. But we had the less osteogenic potential of cells when compared with the enzymatic method.

Conclusion: The current protocol based on the sonication-mediated cavitation is a rapid, safe and cost-effective method, which is proposed for isolation of SVF and of course ADSCs cultures in a large scale for the clinical trials or therapeutic purposes.

Isolation and culture of primary rat adipose derived stem cells using porous biopolymer microcarriers

Adipose-derived stem cells (ADSCs) are an attractive source of material for mesenchymal stem cell research due to the abundance of adipose and relative ease of access compared with bone marrow. A key consideration for research is whether cell isolation methods can be improved, to reduce the process steps needed to isolate and expand cell material. In the current study, we used macroporous biopolymer microcarriers to isolate primary ADSCs. We found that the method was capable of isolating ADSCs that were subsequently capable of being transferred to culture dishes and expanded in vitro. Moreover, flow cytometry revealed that they expressed typical stem cell markers and were capable of undergoing tri-lineage differentiation. In summary, it is feasible to use biopolymer microcarriers for retrieval of viable ADSCs that retain identity markers of stem cell function.

Cell-based strategies for vascular regeneration

Vascular regeneration is known to play an essential role in the repair of injured tissues mainly through accelerating the repair of vascular injury caused by vascular diseases, as well as the recovery of ischemic tissues. However, the clinical vascular regeneration is still challenging. Cell-based therapy is thought to be a promising strategy for vascular regeneration, since various cells have been identified to exert important influences on the process of vascular regeneration such as the enhanced endothelium formation on the surface of vascular grafts, and the induction of vessel-like network formation in the ischemic tissues. Here are a vast number of diverse cell-based strategies that have been extensively studied in vascular regeneration. These strategies can be further classified into three main categories, including cell transplantation, construction of tissue-engineered grafts, and surface modification of scaffolds. Cells used in these strategies mainly refer to terminally differentiated vascular cells, pluripotent stem cells, multipotent stem cells, and unipotent stem cells. The aim of this review is to summarize the reported research advances on the application of various cells for vascular regeneration, yielding insights into future clinical treatment for injured tissue/organ.

Metabolic effects of newly synthesized phosphodiesterase-3 inhibitor 6-[4-(4-methylpiperidin-1-yl)-4-oxobutoxy]-4-methylquinolin-2(1H)-one on rat adipocytes

Background

Clinical use of selective PDE3 inhibitors as cardiotonic agents is limited because of their chronotropic and lipolytic side effects. In our previous work, we synthesized a new PDE3 inhibitor named MC2 (6-[4-(4-methylpiperidin-1-yl)-4-oxobutoxy]-4-methylquinolin-2(1H)-one) which produced a high positive inotropic action with a negative chronotropic effect. This work was done to evaluate the effects of MC2 on adipocytes and compare its effects with those of amrinone and cilostamide.

Methods

Preadipocytes were isolated from rat adipose tissue and differentiated to adipocyte in the presence of cilostamide, amrinone or MC2. Lipolysis and adipogenesis was evaluated by measuring glycerol level and Oil Red O staining, respectively. Adipocyte proliferation and apoptosis were determined with MTT assay and Annexin V/PI staining, respectively.

Results

Differentiation to adipocyte was induced by amrinone but not by cilostamide or MC2. Basal and isoproterenol-stimulated lipolysis significantly increased by cilostamide (p < 0.05). Similarly, amrinone enhanced the stimulated lipolysis (p < 0.01). On the other hand, MC2 significantly decreased both adipogenesis (p < 0.05) and stimulated lipolysis (p < 0.001). Also, incubation of differentiated adipocytes with MC2 caused the loss of cell viability, which was associated with the elevation in apoptotic rate (p < 0.05).

Conclusion

Our data indicate that selective PDE3 inhibitors produce differential effects on adipogenesis and lipolysis. MC2 has proapoptotic and antilipolytic effects on adipocytes and does not stimulate adipogenesis. Therefore, in comparison with the clinically available selective PDE3 inhibitors, MC2 has lowest metabolic side effects and might be a good candidate for treatment of congestive heart failure.

Adipose-derived stromal cell therapy affects lung inflammation and tracheal responsiveness in guinea pig model of COPD

The effects of adipose derived stromal cells (ASCs) were evaluated on tracheal responsiveness and biochemical parameters in guinea pigs model of chronic obstructive pulmonary disease (COPD). Thirty six guinea pigs were divided into 6 groups including: Control, COPD, COPD+intratracheal delivery of PBS (COPD+ITPBS), COPD+intravenous delivery of PBS (COPD+IVPBS), COPD+intratracheal delivery of ASCs (COPD+ITASC) and COPD+intravenous injection of ASCs (COPD+IVASC). COPD was induced by exposing animals to cigarette smoke for 3 months. Cell therapy was then performed and after 14 days, tracheal responsiveness, concentration of interleukin-8 (IL-8) in serum and broncho-alveolar lavage fluid (BALF), as well as total and differential white blood cells (WBC) counts were evaluated. Tracheal responsiveness, total WBC counts, neutrophil and eosinophil percentage in BALF as well as concentration of IL-8 in serum and BALF significantly increased but lymphocyte percentage decreased in COPD compared to the control group (P<0.05 to p<0.001). Cell therapy was able to restore the tracheal hyper-responsiveness and the increased IL-8 concentration in serum and BALF of COPD-ITASC but not COPD-IVASC animals (P<0.05 for all cases). Total WBC in BALF also showed a significant decrease in both treated groups and the percentages of eosinophils, neutrophils and lymphocytes in BALF were reversed in COPD-ITASC compared to COPD-ITPBS animals (P<0.05 to P<0.001). Therefore, intratracheal cell therapy with ASC can decrease tracheal hyperresponsiveness and lung inflammation in cigarette smoke induced-COPD which may be helpful in attenuation of the severity of disease in patients suffering from COPD.

Recent advances of stem cell therapy for retinitis pigmentosa

Retinitis pigmentosa (RP) is a group of inherited retinal disorders characterized by progressive loss of photoreceptors and eventually leads to retina degeneration and atrophy. Until now, the exact pathogenesis and etiology of this disease has not been clear, and many approaches for RP therapies have been carried out in animals and in clinical trials. In recent years, stem cell transplantation-based attempts made some progress, especially the transplantation of bone marrow-derived mesenchymal stem cells (BMSCs). This review will provide an overview of stem cell-based treatment of RP and its main problems, to provide evidence for the safety and feasibility for further clinical treatment.

Autologous platelet-rich plasma: a biological supplement to enhance adipose-derived mesenchymal stem cell expansion

Currently the use of non-autologous cell culture media (e.g., animal-derived or allogeneic serum) for clinical applications of mesenchymal stem cells (MSCs) is criticized by regulatory agencies. Autologous platelet-rich plasma (PRP) is proposed as a safer alternative medium supplement for adipose-derived mesenchymal stem cells (AT-MSC) culture. To study its efficiency on cell proliferation, AT-MSCs were cultured for 10 days in media supplemented with different concentrations of autologous non-activated PRP (nPRP) or thrombin-activated PRP (tPRP) (1-60%). AT-MSC proliferation, cell phenotype, multipotency capacity, and chromosome stability were assessed and compared to AT-MSCs expanded in a classical medium supplemented with 10% of fetal bovine serum (FBS). Culture media supplemented with nPRP showed dose-dependent higher AT-MSC proliferation than did FBS or tPRP. Twenty percent nPRP was the most effective concentration to promote cell proliferation. This condition increased 13.9 times greater AT-MSC number in comparison to culture with FBS, without changing the AT-MSC phenotype, differentiation capacity, and chromosome status. We concluded that 20% autologous nPRP is a safe, efficient, and cost-effective supplement for AT-MSC expansion. It should be considered as an alternative to FBS or other nonautologous blood derivatives. It could serve as a potent substitute for the validation of future clinical protocols as it respects good manufacturing practices and regulatory agencies' standards.

Effects of Securigera securidaca Extract on Lipolysis and Adipogenesis in Diabetic Rats

Diabetes mellitus is associated with dysregulation of adipose tissue metabolism and increased level of serum lipids. In our previous work we found that Securigera securidaca decreases cholesterol level in blood of diabetic rats. The present study was carried out to further investigate the effects of this plant on lipid metabolism, lipolysis, and adipogenesis, in diabetic rats. Female Wistar rats were rendered diabetic by intraperitoneal injection of streptozotocin. Retroperitoneal adipose tissue was removed from diabetic animals after seven days of streptozotocin injection. Effect of hydroalcoholic extract of S. securidaca seeds (100-800 μg/mL) on adipose tissue lipolysis was evaluated in ex vivo condition. Also, to evaluate adipogenesis, preadipocytes were isolated from adipose tissue and differentiated to adipocytes in the presence of the extract. The extract at concentration of 800 μg/mL decreased both basal and catecholamine-stimulated lipolysis (P < 0.05). Incubation of differentiating preadipocytes with 800 μg/mL of S. securidaca extract decreased intracellular lipid droplet accumulation as evaluated with Oil Red O staining (P < 0.001). The extract even at high concentrations had no effect on viability of preadipocytes. In conclusion, S. securidaca decreases lipolysis and adipogenesis without cytotoxicity, which makes it a good candidate for management of dyslipidemia and reduction of cardiovascular risks in diabetes.

Isolation of adipose-derived stromal cells without enzymatic treatment: expansion, phenotypical, and functional characterization

Stem cell therapy is a potential method for the treatment of numerous diseases. The most frequent cellular source is bone-marrow-derived mesenchymal stromal cells (BM-MSCs). Human adipose-derived stromal cells (ADSCs) share similar properties with BM-MSCs as they support hematopoiesis, modulate ongoing immune responses, and differentiate into cells of mesodermal origin. On the other hand, ADSCs have higher frequency in situ, higher availability, and very few ethical issues compared with BM-MSCs, giving them an advantage over BM-MSCs for clinical use. Most of the methods used to isolate ADSCs contain a collagenase digestion step, but the type of collagenase and time of sample digestion vary among studies and these differences could have an impact on the cell properties and thus in result comparison. To overcome this obstacle, we propose a new method to isolate ADSCs from lipoaspirate without collagenase digestion step. We compared ADSCs obtained with our method versus classical protocol using collagenase digestion. Cells obtained with our method are equivalent but they have a better long-term hematopoietic support than those obtained with classical method. Moreover, our method has an advantage over the classical one as it is easier, safer, faster, less expensive, and more consistent with good manufacturing practices to obtain large number of ADSCs ex vivo.

The effect of adipose derived stromal cells on oxidative stress level, lung emphysema and white blood cells of guinea pigs model of chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is a worldwide epidemic disease and a major cause of death and disability. The present study aimed to elucidate pharmacological effects of adipose derived stromal cells (ASCs) on pathological and biochemical factors in a guinea pig model of COPD. Guinea pigs were randomized into 5 groups including: Control, COPD, COPD + intratracheal delivery of PBS as a vehicle (COPD-PBS), COPD + intratracheal delivery of ASCs (COPD-ITASC) and COPD + intravenous injection of ASCs (COPD-IVASC). COPD was induced by exposing animals to cigarette smoke for 3 months. Cell therapy was performed immediately after the end of animal exposure to cigarette smoke and 14 days after that, white blood cells, oxidative stress indices and pathological changes of the lung were measured.

Results

Compared with control group, emphysema was clearly observed in the COPD and COPD-PBS groups (p < 0.001). Lung histopathologic changes of COPD-ITASC and COPD-IVASC groups showed non-significant improvement compared to COPD-PBS group. The COPD-ITASC group showed a significant increase in total WBC compared to COPD-PBS group but there was not a significant increase in this regard in COPD-IVASC group. The differential WBC showed no significant change in number of different types of leukocytes. The serum level of malondialdehyde (MDA) significantly decreased but thiol groups of broncho-alveolar lavage fluid (BALF) increased in both cell treated groups (p < 0.05 for all cases). Weight of animals decreased during smoke exposure and improved after PBS or cell therapy. However, no significant change was observed between the groups receiving PBS and the ones receiving ASCs.

Conclusion

Cell therapy with ASCs can help in reducing oxidative damage during smoking which may collectively hold promise in attenuation of the severity of COPD although the lung structural changes couldn’t be ameliorated with these pharmacological therapeutic methods.